fixed transport.close() call throwing an exception; closes #130

README.md

@@ -55,6 +55,7 @@ new log collection as capped, defaults to false.
 initialization. Works only if __db__ is a string. Defaults to false.
 * __decolorize:__ Will remove color attributes from the log entry message,
 defaults to false.
+* __leaveConnectionOpen:__ Will leave MongoClient connected after transport shut down.
 * __expireAfterSeconds:__ Seconds before the entry is removed. Works only if __capped__ is not set.
 
 *Metadata:* Logged as a native JSON object in 'meta' property.

lib/winston-mongodb.js

@@ -46,7 +46,10 @@ const helpers = require('./helpers');
  * a string.
  * @param {boolean=false} options.decolorize Will remove color attributes from
  * the log entry message.
- * @param {number} options.expireAfterSeconds Seconds before the entry is removed. Do not use if capped is set.
+ * @param {boolean=false} options.leaveConnectionOpen Will leave MongoClient connected
+ * after transport shut down.
+ * @param {number} options.expireAfterSeconds Seconds before the entry is removed.
+ * Do not use if capped is set.
  */
 let MongoDB = exports.MongoDB = function(options) {
   winston.Transport.call(this, options);
@@ -72,6 +75,7 @@ let MongoDB = exports.MongoDB = function(options) {
   this.cappedSize = (options.cappedSize || 10000000);
   this.cappedMax = options.cappedMax;
   this.decolorize = options.decolorize;
+  this.leaveConnectionOpen = options.leaveConnectionOpen;
   this.expireAfterSeconds = !this.capped && options.expireAfterSeconds;
   if (this.storeHost) {
     this.hostname = os.hostname();
@@ -84,7 +88,9 @@ let MongoDB = exports.MongoDB = function(options) {
       self.logDb = db;
       processOpQueue();
     }, err=>{
-      db.close();
+      if (self.mongoClient && !self.leaveConnectionOpen) {
+        self.mongoClient.close();
+      }
       console.error('winston-mongodb, initialization error: ', err);
     });
   }
@@ -120,7 +126,10 @@ let MongoDB = exports.MongoDB = function(options) {
   }
   function connectToDatabase(logger) {
     return mongodb.MongoClient.connect(logger.db, logger.options
-    ).then(client=>setupDatabaseAndEmptyQueue(client.db()), err=>{
+    ).then(client=>{
+      logger.mongoClient = client;
+      setupDatabaseAndEmptyQueue(client.db());
+    }, err=>{
       console.error('winston-mongodb: error initialising logger', err);
       if (options.tryReconnect) {
         console.log('winston-mongodb: will try reconnecting in 10 seconds');
@@ -133,11 +142,16 @@ let MongoDB = exports.MongoDB = function(options) {
   if ('string' === typeof this.db) {
     connectToDatabase(this);
   } else if ('function' === typeof this.db.then) {
-    this.db.then(client=>setupDatabaseAndEmptyQueue(client.db()), err=>console.error(
-        'winston-mongodb: error initialising logger from promise', err));
+    this.db.then(client=>{
+      this.mongoClient = client;
+      setupDatabaseAndEmptyQueue(client.db());
+    }, err=>console.error('winston-mongodb: error initialising logger from promise', err));
   } else if ('function' === typeof this.db.db) {
+    this.mongoClient = this.db;
     setupDatabaseAndEmptyQueue(this.db.db())
   } else { // preconnected object
+    console.warn(
+      'winston-mongodb: preconnected object support is deprecated and will be removed in v5');
     setupDatabaseAndEmptyQueue(this.db);
   }
 };
@@ -161,10 +175,11 @@ winston.transports.MongoDB = MongoDB;
  * Used by winston Logger.close on transports.
  */
 MongoDB.prototype.close = function() {
-  if (!this.logDb) {
+  this.logDb = null;
+  if (!this.mongoClient || this.leaveConnectionOpen) {
     return;
   }
-  this.logDb.close().then(()=>this.logDb = null).catch(err=>{
+  this.mongoClient.close().then(()=>this.mongoClient = null).catch(err=>{
     console.error('Winston MongoDB transport encountered on error during '
         + 'closing.', err);
   });

test/winston-mongodb-test.js

@@ -17,6 +17,15 @@ const dbUrl = process.env.USER_WINSTON_MONGODB_URL
 
 mongoose.connect(dbUrl);
 
+describe('winston-mongodb-manual-tests', function() {
+  describe('winston-mongodb', function() {
+    let transport = new MongoDB({db: dbUrl});
+    it('should be closeable', function() {
+      transport.close();
+    });
+  });
+});
+
 test_suite({name: '{db: url}', Transport: MongoDB, construct: {db: dbUrl}});
 test_suite({name: '{db: url} on capped collection', Transport: MongoDB,
     construct: {db: dbUrl, capped: true, collection: 'cappedLog'}});